Plants of the Week – August 20

Curcuma, derived from the Arabic word kurkum, meaning turmeric, was first described by Linnaeus in 1753. Curcuma ‘Sulee Sunshine’ is a hybrid from Thailand developed for the cut flower industry. Otherworldly looking flowers, often referred to as cones, emerge in August and continue through October. Unlike other curcumas which hide their flowers amongst foliage, Curcuma ‘Sulee Sunshine’ bears leaves which natuarally fold away serving as a brilliant background to highlight the inflorescence. A specimen can be seen growing along the bluestone path near the Off-Campus Study Office in the Terry Shane Teaching Garden. Photo credit: J. Coceano

Pycnanthemum muticum always generates numerous questions at this time of year. Two masses growing under large Pinus nigra are cloaked in bloom and equally covered in a bevy of pollinators. A plethora of bees, wasps, and flies can be observed zipping from one flower to the next. Silvery bracts surround tiny flowers atop plants reaching 2 feet in height. Interestingly North Creek Nursery shares that P. muticum contains pulegone, the same insect repellent found in pennyroyal and can be rubbed on the skin to repel mosquitoes. Photo credit: J. Coceano

With a casual glance one would likely never realize that Acer carpinifolium is indeed a maple. The hornbean maple, a native of Japan, has leaves more akin to Carpinus carolinana than Acer. Samaras, the distinct winged seeds, are the only indication of its true identity. Trees typically grow 20-25’ tall and are vase-shaped with a rounded profile. Bright yellow fall color develops as the days shorten. Photo credit: J. Coceano

The family Rutaceae is typically known for its tropical and Mediterranean members, particularly those in the Citrus genus: oranges, lemons, limes, and kumquats to name a few. There are several lesser known members that have shown promise, successfully overwintering in the greater Philadelphia area including Orixa japonica ‘Pearl Frost’. This deciduous shrub can reach upwards of 10’ in height sporting eye-catching variegated foliage. The leaves remain bright and clean throughout the summer months, never fading. Partially shaded areas make ideal growing conditions and allow the leaves to provide illumination. Photo credit: J. Coceano